go-ethereum/eth/tracers/native/noop.go
Sina M 064f37d6f6
eth/tracers: live chain tracing with hooks (#29189)
Here we add a Go API for running tracing plugins within the main block import process. 

As an advanced user of geth, you can now create a Go file in eth/tracers/live/, and within
that file register your custom tracer implementation. Then recompile geth and select your tracer
on the command line. Hooks defined in the tracer will run whenever a block is processed.

The hook system is defined in package core/tracing. It uses a struct with callbacks, instead of 
requiring an interface, for several reasons:

- We plan to keep this API stable long-term. The core/tracing hook API does not depend on
  on deep geth internals.
- There are a lot of hooks, and tracers will only need some of them. Using a struct allows you
   to implement only the hooks you want to actually use.

All existing tracers in eth/tracers/native have been rewritten to use the new hook system.

This change breaks compatibility with the vm.EVMLogger interface that we used to have.
If you are a user of vm.EVMLogger, please migrate to core/tracing, and sorry for breaking
your stuff. But we just couldn't have both the old and new tracing APIs coexist in the EVM.

---------

Co-authored-by: Matthieu Vachon <matthieu.o.vachon@gmail.com>
Co-authored-by: Delweng <delweng@gmail.com>
Co-authored-by: Martin HS <martin@swende.se>
2024-03-22 18:53:53 +01:00

99 lines
3.3 KiB
Go

// Copyright 2021 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
package native
import (
"encoding/json"
"math/big"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/core/tracing"
"github.com/ethereum/go-ethereum/core/types"
"github.com/ethereum/go-ethereum/eth/tracers"
)
func init() {
tracers.DefaultDirectory.Register("noopTracer", newNoopTracer, false)
}
// noopTracer is a go implementation of the Tracer interface which
// performs no action. It's mostly useful for testing purposes.
type noopTracer struct{}
// newNoopTracer returns a new noop tracer.
func newNoopTracer(ctx *tracers.Context, _ json.RawMessage) (*tracers.Tracer, error) {
t := &noopTracer{}
return &tracers.Tracer{
Hooks: &tracing.Hooks{
OnTxStart: t.OnTxStart,
OnTxEnd: t.OnTxEnd,
OnEnter: t.OnEnter,
OnExit: t.OnExit,
OnOpcode: t.OnOpcode,
OnFault: t.OnFault,
OnGasChange: t.OnGasChange,
OnBalanceChange: t.OnBalanceChange,
OnNonceChange: t.OnNonceChange,
OnCodeChange: t.OnCodeChange,
OnStorageChange: t.OnStorageChange,
OnLog: t.OnLog,
},
GetResult: t.GetResult,
Stop: t.Stop,
}, nil
}
func (t *noopTracer) OnOpcode(pc uint64, op byte, gas, cost uint64, scope tracing.OpContext, rData []byte, depth int, err error) {
}
func (t *noopTracer) OnFault(pc uint64, op byte, gas, cost uint64, _ tracing.OpContext, depth int, err error) {
}
func (t *noopTracer) OnGasChange(old, new uint64, reason tracing.GasChangeReason) {}
func (t *noopTracer) OnEnter(depth int, typ byte, from common.Address, to common.Address, input []byte, gas uint64, value *big.Int) {
}
func (t *noopTracer) OnExit(depth int, output []byte, gasUsed uint64, err error, reverted bool) {
}
func (*noopTracer) OnTxStart(env *tracing.VMContext, tx *types.Transaction, from common.Address) {
}
func (*noopTracer) OnTxEnd(receipt *types.Receipt, err error) {}
func (*noopTracer) OnBalanceChange(a common.Address, prev, new *big.Int, reason tracing.BalanceChangeReason) {
}
func (*noopTracer) OnNonceChange(a common.Address, prev, new uint64) {}
func (*noopTracer) OnCodeChange(a common.Address, prevCodeHash common.Hash, prev []byte, codeHash common.Hash, code []byte) {
}
func (*noopTracer) OnStorageChange(a common.Address, k, prev, new common.Hash) {}
func (*noopTracer) OnLog(log *types.Log) {}
// GetResult returns an empty json object.
func (t *noopTracer) GetResult() (json.RawMessage, error) {
return json.RawMessage(`{}`), nil
}
// Stop terminates execution of the tracer at the first opportune moment.
func (t *noopTracer) Stop(err error) {
}